There are a number of manifold and filtration devices used in combination with commercially available medical waste collection systems.
In U.S. Pat. No. 7,497,340 the inventors recite a list of medical waste collection units. Examples of waste collection units can be found in U.S. Pat. Nos. 5,997,733; 6,180,000; and 6,222,283. For instance, U.S. Pat. No. 5,997,733 discloses a waste liquid and smoke disposal system which combines the functions of a smoke extraction system and a waste collection unit, typically in, but not limited to, a surgical environment. The smoke extraction system and the waste collection unit are connected to supply the medical waste collected thereby to a waste treatment (e.g. decontamination and/or sterilization) and disposal system. In such systems, the waste collection unit can be provided as a cart-mounted apparatus to provide mobility. The waste collection unit can then dock to known docking stations to dispose of the medical waste collected by the unit. As a result, surgical teams can quickly, easily, and efficiently maintain the integrity of a surgical site with a minimum of operating components.
Disposable manifold and filter assemblies are used to facilitate the collection of the medical waste into the waste collection unit. Typically, the manifold and filter assembly includes at least one filter to remove solid or semi-solid material such as bone chips, flesh, blood clots or the like from the liquid medical waste generated by the surgical procedure or operation. Preferably, the single use manifolds are disposed of between patients, or when the manifold is spent, i.e., filled with solid and semi-solid materials. An example of a disposable manifold for use in waste collection units is described in U.S. Pat. No. 6,331,246 to Beckham et al. This Beckham et al patent discloses a manifold and filter assembly for use with a waste collection unit to filter medical waste generated during a medical process. The manifold and filter assembly includes a manifold housing, inlet ports, an outlet port, and a series of filters disposed between the inlet and outlet ports. The filters retain solid and semi-solid materials from a fluid carrier entering the manifold housing through the inlet ports. Check valves are placed on the inlet ports to establish unidirectional flow. Currently, once the filters are plugged with debris, the manifold housing begins to fill with the medical waste. The check valves ensure that the medical waste does not reverse flow into the inlet ports.
One of the first medical waste collection units was a product called the Neptune® Waste Management System, a commercially available waste collection and disposal device. The Neptune® System was designed and manufactured by a company called American Immuno Tech, Costa Mesa, Calif., and Stryker® eventually acquired the product from American Immuno Tech and all patents and IP became property of Stryker®.
The Neptune® System has an independent vacuum pump on the unit which suctions fluid from a surgical field and collects it in a large 20 Liter canister which is later disposed of following a surgical procedure. The Neptune® System is typically used in high fluid procedures such as arthroscopies. A “single use” fluid manifold is used in conjunction with the Neptune® System to filter solid particulate matter from the liquid so the canister does not become overburdened with debris.
American Immuno Tech was granted a patent for an original manifold design on Dec. 18, 2001. This manifold, of U.S. Pat. No. 6,331,246, can be clogged very badly as a result of a poor design. Specifically, the “Duck Billed” anti-reflux valves located on the manifold ports clogged causing Neptune® System to lose vacuum pressure. If the manifold body got too full of debris, the Neptune® System could lose all vacuum pressure and render the entire system useless.
Improvements were made to the original '246 manifold design by a company called Stryker® and the later versions worked better and clogged less. One of the new manifolds is disclosed in U.S. Pat. No. 7,163,618.
In February of 2004 a next generation, third manifold was introduced to the market by Stryker®. It was of a completely different design than the previous two versions of manifolds and performed well. This third manifold was awarded a grant of U.S. Pat. No. 7,497,340.
Additionally, a forth manifold was introduced by Stryker® which has a single port on the manifold body so only one suction line can be attached to the manifold versus the four ports on all other designs. This manifold was called “The Single Port” manifold and was offered to the market as a cost savings alternative to the four port options. A patent was granted for this design, U.S. Pat. No. 6,902,673.
All of these prior art manifolds suffer from high levels of design complexity and require numerous components adding to cost. When disposable devices, best suited for single use, cost too much there is a tendency for the end user to want to clean and reuse the device. These prior art manifolds by having so many separate plastic molded parts assembled together results in increased material weight and cost.
A more important issue is when the multiport manifold with filtration devices clogs a potential risk exists where the multiport vacuum ports reverse flow causing the waste fluids to back into the vacuum lines and into an open surgical site. As repulsive as this seems it is also very dangerous from a contamination perspective.
This is a real concern and has led to numerous design changes in multiport manifolds. In U.S. Pat. No. 7,497,340 a bypass is included to prevent medical waste from reaching the inlet ports. By providing this fluid bypass, the manifold and filter assembly of this prior art invention eliminates the backup of the medical waste to the inlet thereby allowing the medical waste to continually flow through the manifold and filter assembly even when the manifold and filter assembly is spent, i.e., the filter basket is filled. The filter basket includes a plurality of openings to filter the medical waste in the fluid path between the inlet and the outlet. The plurality of inlet ports has ends that are centrally located aligned in a horizontal row spaced above the basket and the waste products drop into the basket to be filtered. The filter basket is spaced from the manifold housing to create a fluid bypass between the filter basket and the manifold housing. The fluid bypass is in fluid communication with the outlet whereby the excess medical waste can overflow over the peripheral wall to the outlet through the fluid bypass when the filter is full and virtually useless.
This prior art design has an end cap that can be reopened and the contents of the filter basket dumped and the cap easily snapped back on means it is tempting to reuse this device. Reuse is exacerbated by the high cost of this multiport design. More importantly, the overfilling of the filter basket is common as the device is so costly it is desirable to completely fill the basket before replacing it. This means unfiltered debris is going directly into the collection unit.
It is therefore an object of the present invention to greatly increase the volume of debris a multiport manifold can retain without blocking the device. A further object is to insure the device is difficult to reuse. Another objective is to provide a positive indication that the device has been previously used.
Other objectives are to simplify the design, reduce the raw material and components needed to manufacture the device, provide the device at a low cost for single use and to make it so inexpensive it would be foolish to attempt to reuse it.
These and other objectives are achieved by the device and described as follows.